Resolves issue apache#11292 where Maven shows '[unknown project]' in error
messages when using -e -X flags, particularly in CI environments.

The issue occurred because DefaultProjectBuilder was creating
DefaultProjectBuildingResult with null project information when
ModelBuilderResult.getEffectiveModel() returned null, resulting in
empty projectId and causing ProjectBuildingException.createMessage()
to display '[unknown project]' as a fallback.

This fix extracts project identification from available model data
(rawModel or fileModel) when effectiveModel is null, following the
same pattern used in ModelBuilderException.getModelId().

Changes:
- Added extractProjectId() helper method that falls back to rawModel
  or fileModel when effectiveModel is null
- Modified project building result creation to use extracted projectId
  and POM file information instead of null values
- Maintains backward compatibility: when all models are null, still
  returns empty string to preserve '[unknown project]' fallback for
  truly unknown projects

This provides better error messages showing meaningful project
identification like 'com.example:my-project:jar:1.0.0' even when
project building fails, while maintaining existing error handling
patterns.

(cherry picked from commit cb5ee55)